Cabin By The Lake

It tells the story of Stanley, played by Judd Nelson, a script writer who begins killing girls for research for a movie he is writing, where the villain does the same thing.
Synopsis
The movie takes place in Summit Lake, where Stanley is renting a cabin to write a script for a new movie where a killer drowns young girls and keeps them underwater as a macabre garden. The last girl he captures, Mallory, is rescued right after Stanley drops her in the water by his friends, a police officer named Steve and a couple who owns a movie special-effects shop nearby.Mallory then gives the idea to make a plaster-mold of herself, with a camera as an eye, to catch the killer when he returns to his garden. When Stanley returns to the bodies, he soon discovers the ploy, and quickly escapes, and due to wearing a scuba mask, his identity remains unknown.
Mallory, assuming herself safe, stays at a hotel room for the night, but is again captured by Stanley while in the bathtub.He kills the director with a cleaver, then imprisons Regan with Mallory. He then takes them both to the lake to drown them, but Steve and the other police dive and quickly release them, while Stanley is trapped underwater with a rope around his leg.He is assumed dead, as Mallory tries to recover from the experience, still seeing his face in the water.
The last scene has a person talking to a new agent about a movie in which a killer buries his victims alive. The agent asks the person how the person feels as they're buried alive.